Corner joint structure for knockdown boxes



y 1951 P. L. VON CANON 2,551,775

CORNER JOINT STRUCTURE FOR KNOCKDOWN BOXES Filed Nov. 22, 1946 2 Sheets-Sheet l Z'mventor attorney 8 y 1951 v P. L. VON CANON 2,551,775

CORNER JOINT STRUCTURE FOR KNOCKDOWN BOXES Filed Nov. 22, 1946 2 Sheets-Sheet 2 Bummer I 64 4 01 1 wz wm CZ-Me Patented May 8, 1951 CORNER JOINT STRUCTURE FOR KNOCKDOW N BOXES PaulL. Von Canon, West End, N.

Application November 22, 1946, Serial No. 711,567

2. Claims.

be interconnected by a relative rotary movementof the side pieces: of the box when their ends are first brought together in angular positions and one of. them is rotated: into a position of 90- with respect: to the other.

Another feature of my invention. is the provision: of two complementary joints; of different forms respecl-ive'ly located atdiagonal corners of the box frame each. comprising; interlocking: tongues and grooves which when the ends of the four side pieces of the box are placed together rhomboidally interengage; when. saidpieces are simultaneously adjusted into rectangular position.

A still further object of the invention is: to provide forms. of jointsv which. may be used in duplicate for-effecting connection between the forward ends of drawerside pieces. and: the drawer front which will: both cheapen and improve. the construction of furniture drawers per se.

To these'and other ends: my inventionembodies further improvements all: of which will befully described in the accompanying specification, the: novel features thereof being set forth in the ap-- pended claims.

In the drawings:

Figure 1 is a plan View of a box or drawer frame in which the four sides are connected in accordance with the method comprising m invention.

Figure Zisa view illustrating. the form of. framing joints employed in carrying out my invention and the method of interlocking the four corners of a box or drawer.

Figure 3 is a side elevation showing a drawer with the bottom attached which. permanently secures the side pieces in their assembled position.

Figures. 4. and 5 are fragmentary views illustrating the assembly of furniture drawer side pieces and the drawer front embodying the two forms of framing joints, the former showing the joint requiring the. side pieces. to. be revolved outwardly and the other in which the side pieces are secured in position by rotating their free ends in a direction inwardly or toward each other.

Figure 6 is a detail of the end piece showing its attachment to the free ends of drawer side 2 pieces for holding the latter in locked: position.

Similar reference characters in the sevcrai fig:-- ures indicate similar parts. I

In the construction of certain types of boxes: and especial-lydrawers for furniture, it is often. desirable to finish the several. pieces which com pose the completed. article at the: mill and assemble them at other points. To facilitatetheir manufacture. and assure that when. the. several. side pieces are brought together in. finaliformthey' willv fit precisely to form a perfectly rectangular structure, 13 have provided unique forms: of complemertary' joints which are adapted to interlock at the four corners when the several side pieces are brought together by a relative rotary movementwhich is effected in a single operation..

In order to illustrate my invention I have shown in Fig. I a rectangular frame comprising the side pieces I and Z and. end pieces. 3. and, These. were assembled by first placing them with their beveled or miter-ed. ends in juxtaposition to form a rhomboid' as shown: in Fig... 2, and subse: quently straightening up this geometrical figure sothat the adjoining ends of the several pieces are each at right angles.

The interlocking of the several corners. is; aocomplished by providing the diagonal corners with two different. pairs of joints generally coma prising: interengaging tongues and: grooves. formed in conjunction with the miteredi faces. on. the ends of thef'o-ur side pieces of the box or drawer.

At two of the opposed corners, indicated by-a and b it wi l]; be observed that when the. ends of the side and end. pieces. are. brought into juxtaposition at an anglev to each other. the. mitered faces 5 and 6. and l and; 8 enga e. at their inner points, forming angles which diverge outwardy. Likewise the m-itered-l faces. 3'--l:0: and; il -t2: at: the remaining corners c and d engage: at their outer points. forming converging angles.

At the corners. a and 6 IV form on one: off they inner faces such as: 5 andiB tongues l3 and M and on the other faces. grooves 15 and I5, said tongues. and grooves each having their shoulder portions curved, thus forming on the tongues. undercuts and on inner sides. of the. grooves shoulders H fitting therein. when one side is rotated relative to its adjoining pieces and serving to prevent pulliing them apart. The peripheries of the tongues and the bottoms of the grooves are crownedso as to fit neatly one within the other to provide. close fitting surfaces.

- Since; at. the corners; cand d the anglesformeciby the mitered faces are on lines which diverge inwardly I employ a difierent formof look at these points, whereas the tongues and grooves first described at corners a and b are shaped with reference to the pivotal action of the side pieces occurring at the meeting points at the inner ends of the miters the tongues and grooves at the corners c and d are shaped with reference to the outer points of these miters. Consequently at the bases of miter faces 9 and I2 I cut an ogee shaped face' |8 the outer point IQ of which projects slightly beyond the mitered face while its inner end terminates at and defines the inner edge of a plane 20 well within the plane of the mitered surface. Midway of this plane 20 a groove 2| is out. To fit the recesses thus formed there are formed on the complementary mitered faces and II a corresponding stepped projection 22 carrying a tongue 23 and having an ogee curved face 24, the inner edge of which forms a shoulder 25. The proportion of these parts is such that when the box or drawer side piece are adjusted from the rhomboid shown in Fig. 2 to the rectangular position of Fig. l, the bringing together of the mitered faces will also cause the tongues 23 to fit within the grooves 2|. This movement of the parts also brings into engagement the similarly shaped ogee surfaces, the overlapping parts of which prevent the separation of the box side pieces in one direction while the interfitted tongues and grooves prevent their being pulled apart in the other direction.

In accomplishing the foregoing interfitting of the parts it is realized first that the parts being of wood, when the outer corners of the notches 2| and 23 engage they will each yield sufficiently to interlock without chipping even if the pivotal action about the outer corners c and d is alone depended upon. However, what may actually happen and probably does occur in the many instances, as I have demonstrated in practice by making the joints illustrated of metal, is that when the tongue 23 engages the surface at the proximate corner of the groove 2| the portion ll of the miter moves slightly along the miter portion |2 until the lower point of the ogee 24 engages the ogee [8. At such time the relative angular position of the side pieces 2-3 and |--4 are so nearly at right angles to each other that the parts readily slip into their position of final engagement. Even though the interfitting of the above parts and also the positioning of the projections IT in the grooves beneath the tongues H is accomplished as a result of the yielding of the wood fibers no damage results as the interlocking has been accomplished and it is not contemplated that the joints will ever be opened.

It will be seen from the foregoing that I have provided a means for connecting the four sides of a box or drawer whereby it may be assembled without the use of tools or templates, its final shape being assured by the complementary construction of the corner joints, the rectangular assembly being maintained by the bottom 26 which is subsequently attached to the lower edges of the side pieces, in the case of a drawer, or by both the top and bottom closures afiixed thereto in the case of a box. The closely fitting parts of the several joints may if desired also be firmly united by the application of cement or glue to the surfaces before they are united, as will b understood.

Both of the joints above described may be used in pairs in the construction of furniture drawers, as shown in Figs. 4 and 5, for connecting side pieces to a drawer front. For example I have shown in Fig. 4 a drawer front 30 and side pieces 3|32 provided respectively with the tongues and grooves employed at the corners a and b of Figs. 1 and 2. These are brought into interlocking engagement by positioning the side pieces first in the dotted line position and rotating their free ends outwardly at right angles to the front piece 30. Again in Fig. 5 I have shown the joint construction used at the corners c and d of Figs. 1 and 2 forming the framing connections between the ends of a drawer front 35 and the side pieces 363'| which are interengaged by swinging the free ends of the side pieces from the dotted line position to that shown by the full lines.

In both of these assemblages the free ends of the side pieces are connected at their rear or free ends by a back piece 40 which may be mortised or otherwise attached to them as shown in Fig. 6. It will also be understood that in these constructions the drawers are provided with a bottom which is subsequently attached and correspond to the part indicated by 26 in Fig. 3.

I claim:

A knockdown box comprising four side pieces having mitered end faces, two of which when said pieces are assembled in the form of a rhomboid engage at their inner points and two engage at their outer points, said inner engaging faces being provided respectively with tongues and grooves having curved surfaces shaped to form cooperating undercuts and shoulders, said outer point engaging faces being respectively provided with lateral stepped undercuts provided with grooves and similar projections provided with tongues, the several tongues and grooves on the several faces being formed to interlock upon relative rotative movement of the parts to bring them into rectangular form.

2. A knockdown box comprising four side pieces having end faces which unite to form a rectangular structure, the end faces of one pair of diagonally opposite corners being provided respectively with tongue and grooves having curved surfaces shaped to form cooperating undercuts and shoulders, the faces of the other pair of diagonally opposite corners being respectively provided with lateral stepped undercuts provided with grooves and similar projections provided with tongues, the several tongues and grooves on the several faces being formed to interlock upon relative movement of the side pieces from a rhomboidal position of assembly into a rectangular position.

PAUL L. VON CANON.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 372,694 Mergott Nov. 8, 1887 1,070,572 Wyckoff Aug. 19, 1913 1,159,229 Keith Nov. 2, 1915 1,533,099 Carroll Apr. 14, 1925 1,922,994 Voigt Aug. 14, 1933 2,002,228 Meyercord et al. May 21, 1935 2,453,918 Jansen NOV. 16, 1948 FOREIGN PATENTS Number Country Date 83,681 Switzerland W Dec. 30, 1918 

